JSON Studio

JSON Smart Repair Engine

Smart AI Repair

Automatically fix trailing commas, single quotes, unquoted keys, Python dict literals, comments, and missing brackets.

Processed 100% locally in your browser
Tip: Upload broken .json files directly or paste stringified payloads to repair syntax instantly.
Broken / Malformed JSON
182 chars
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Repaired Valid JSON
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Online JSON Repair Engine & Syntax Fixer

Struggling with invalid JSON syntax errors? alpha-json Smart Repair Engine automatically detects and fixes broken JSON formatting, converting malformed payloads into strict RFC 8259 compliant JSON.

Fix Python Dict Literals

Automatically converts Python True, False, and None values into standard JSON true, false, and null.

Quote Keys & Single Quotes

Converts unquoted JavaScript keys (e.g. foo: 'bar') and replaces single quotes with double quotes.

Remove Comments & Trailing Commas

Strips single-line (//) and block (/* */) comments and trailing commas in arrays and objects.

Technical Documentation & Reference

Complete Guide to Automated JSON Syntax Repair

Learn how AST-based heuristics repair malformed JSON payloads, convert Python dictionary literals, and strip invalid comments without data corruption.

In real-world development, JSON payloads frequently arrive corrupted or improperly formatted: Python code outputs string representations of dictionaries containing single quotes and capitalized booleans (True, False, None); developers manually edit configuration files and leave trailing commas; or API logs contain unquoted object keys and C-style comments (// or /* */).

Standard JSON parsers fail catastrophically on any of these errors. Rather than manually editing hundreds of lines or writing error-prone regex replacements, JSON Studio's Pure AST Repair Engine parses malformed tokens and repairs them in a single pass into fully compliant RFC 8259 JSON.

What Can the Auto-Repair Engine Fix?

  • Single to Double Quotes: Converts single-quoted strings and keys into standard double quotes while safely escaping nested quotes.
  • Python Dictionary Literals: Converts Python True to true, False to false, and None to null.
  • Trailing Commas: Removes invalid trailing commas in arrays and objects.
  • Unquoted Object Keys: Quotes unquoted JavaScript object keys (e.g. { user_id: 12 } becomes { "user_id": 12 }).
  • Comments Stripping: Safely removes single-line (//) and multi-line (/* */) comments without corrupting URLs inside strings.
  • Missing Closing Brackets: Automatically appends missing closing braces and brackets at the end of truncated files.

How to Use This Tool

1

Paste Malformed Payload

Paste your broken JSON, Python dict string, or truncated log file into the left editor.

2

Click Auto-Repair JSON

Click the Auto-Repair button to trigger the multi-stage AST repair pipeline.

3

Review Clean Formatted Output

Inspect the repaired, properly formatted JSON output in the right editor with full syntax highlighting.

4

Copy or Download Clean File

Export the valid JSON payload directly to your clipboard or download as a .json file.

Key Features & Capabilities

Multi-Pass Repair Pipeline

Combines tokenization, string normalization, and bracket balancing in a high-speed, zero-DOM pipeline.

URL-Safe Comment Stripper

Intelligently differentiates between inline code comments and URL protocol slashes (http://).

Python Dict to JSON Translation

Effortlessly convert Python print(dict) outputs directly into standard JSON format.

100% In-Browser Privacy

Repair internal configuration files and database exports without sending data over the network.

Frequently Asked Questions

How does the repair engine differentiate comments from URLs?
The repair engine uses a state-aware tokenizer that tracks string literal boundaries. Slashes inside double or single quotes (like https://example.com) are preserved, while slashes outside string literals are treated as comments and stripped.
Can this repair Python dictionary strings?
Yes! It converts Python single-quoted keys and values to double quotes, and replaces True, False, and None with true, false, and null.
What happens if a JSON payload is cut off at the end?
The repair engine calculates the unmatched opening braces "{" and brackets "[" and appends the appropriate closing tokens at EOF.
Is any of my data transmitted to a server during repair?
No. The repair engine is a pure TypeScript algorithm running entirely in your browser JavaScript environment.

Privacy & Security Guarantee

All data processing, AST syntax repairs, and cryptographic operations happen 100% locally inside your browser using native JavaScript and WebAssembly. No inputs, keys, or file payloads are ever transmitted to or stored on remote servers.